Hybrid ferry statistics please Kitsap Transit

BREMERTON - A hybrid propulsion system for a soon-to-be-built Sinclair Inlet ferry could pay for itself in three to 5 1/2 years, marine engineers told the Kitsap Transit board Tuesday.

The agency plans to build a clone of its 120-passenger Admiral Pete, but is determining whether there's a better way to power it. The two catamarans would provide the bulk of service on the Port Orchard-Bremerton and Annapolis-Bremerton routes.

Kitsap Transit hired Bremerton marine engineering firm Art Anderson Associates to examine alternatives to a traditional diesel engine. It found just one "turnkey" hybrid system in which all of the components were provided by one vendor — Northern Lights Inc. of Seattle, said Ralph Duncan, Art Anderson Associates vice president of marine engineering and research.

In a diesel-electric system, the diesel engine isn't attached to the propeller. It powers the batteries. It senses when they need charging and only operates then. The batteries power the prop. The diesel engine in the new sister ferry would only run while it's crossing the bay, then switch to battery power at the docks.

The Admiral Pete doesn't use all of its 810 horsepower and doesn't operate at its peak. The hybrid engine, at just 530 horsepower, would always run at the most efficient point, Duncan said, and would only be running one-third of the time. Fuel savings would be about $45,000 a year, he said.

The hybrid system would cost $400,000 more to purchase than a traditional diesel engine. With the savings on fuel and maintenance costs, it would take Kitsap Transit three to 5 1/2 years to break even. After that, the hybrid could save the agency $700,000 to $1.5 million over a 20-year life, Duncan said.

Emissions would be reduced 53 percent to 67 percent.

The next step will be to define the propulsion system redesign and begin developing pricing and construction plans for a new ferry. The transit board passed a resolution Tuesday to provide $100,000 over the next two years for an owner's representative to oversee the process. A request for proposals will be published with a winner based on qualifications and price.

Kitsap Transit Executive Director John Clauson said he and the agency's passenger ferry subcommittee will discuss the ferry in more detail at their next meeting. There are several factors to be taken into account, but so far the idea looks good.

"I'm extremely pleased with the results we saw today," he said. "Certainly on the surface it looks like this is something we should really pursue. If we are able to come up with a vessel that will be less expensive to operate for the next 10, 15 or 20 years, that's something we need to take a long, hard look at."